Julian Glover is right to urge restraint in the west's response to the cargo bomb plot. Anyone who calls for military intervention in Yemen has failed to learn the lessons of the Iraq war, which gave al-Qaida a recruitment boost that it draws strength from even to this day. But the need to protect our interests in the skies has never been greater. It is time for aviation officials to stop whining about the economic fallout of security checks, and wake up to the game-changing nature of the threat these new devices pose.

Michael O'Leary's appearance on the BBC this morning epitomised just how reluctant the industry is when it comes to acknowledging the risks, even in the face of irrefutable evidence. "These [bombs] haven't been on passenger airplanes," the Ryanair chief insisted when asked about the dangers to the flying public. Of course we know this is simply not true – one of the devices was bundled on to two scheduled flights before eventually being found in Dubai, and indeed globally around half of all cargo packages are now transported on passenger jets. "There hasn't been a breach of any European airport security," O'Leary shrugged, refusing to diagnose the flying of military-grade explosives into East Midlands Airport for what it clearly is – a flagrant and deeply troubling breach of European airport security.

More delusional still was his misguided reassurance that "there has been no terrorist attack on a European passenger aircraft for many years". Relatives of the 89 people who died in the suicide bombing of two passenger jets that departed from Moscow International Airport in August 2004 would surely beg to differ.

There is something deeply unsettling about this gut reaction among industry officials to downplay the scope of the parcel bomb threat. If the west is to keep its response proportionate and measured, it surely befalls authorities to scrutinise and digest the objective dangers we face. As Glover put it, we must "make a series of sensible factual observations" before we decide how to react. I question whether this has been done. I question, for example, why BA chairman Martin Broughton called for certain airport security checks to be scaled back last week, when he would have known full well that al-Qaida in the Arabian Peninsula had succeeded in smuggling explosives on to two aircraft since last autumn – not just the Detroit-bound plane on Christmas Day but, even more astoundingly, a private jet owned by none other than the head of Saudi Arabia's counter-terrorism agency.

Let's focus on the evidential capabilities of al-Qaida for a minute, rather than getting lost in the broader ideological landscape. In the seven years immediately following 9/11, we know there was only one reported incident of the terror group smuggling explosives on to a plane. Shoe-bomber Richard Reid failed in that attempt – his only victory being the imposition of one of countless new security measures to which Broughton and O'Leary are so opposed. But stay focused on the facts. In the subsequent two years – 2009 and 2010 – al-Qaida's success rate appears to have rocketed. The organisation has managed to smuggle bombs on to at least four different aircraft – passenger jets, cargo jets, even private jets belonging to the Saudi royal family. It has done so by developing PETN bombs so advanced that our scanners and sniffer dogs are seemingly incapable of detecting them.

Even when our security apparatus was tipped off about the UPS bomb, even when we were spoon-fed the tracker number of the offending package, and even when our bomb disposal experts stared the device squarely in the eyes, still we gave it the all-clear. That has never happened before. That is a game-changing development in the threat we face. And it's an error of judgment which I worry is symptomatic of the all-clear O'Leary, Broughton and many others are now rushing to give.

If assessing the threat objectively seems difficult, then diagnosing the remedy is nigh on impossible. With so many different voices clamouring for attention, and with the sanctity of so many basic human rights – security, liberty, privacy – at stake, this is a balancing act few of us would wish to undertake. But respond we must, and instead of brushing worst-case scenarios aside, the industry needs to bite the bullet and face up to its responsibilities urgently, while fortune is still on its side.

Renewing our focus on freight must unquestionably be a priority, but we have to recognise the bigger picture here – targeting cargo planes was just the latest in a long line of diversification by al-Qaida. If we ban shipments from Yemen, the terrorists will load them on to planes in the UAE, or Bahrain. If we ban all cargo from commercial planes, the militants will go back to the drawing board and develop new body bombs. The game of cat and mouse is destined to continue indefinitely.

It's regrettable, then, that the closest we have to a solution, and an approach which the industry is understandably hostile towards, is that we continue rolling out burdensomely invasive, multi-layered security checks. They're costly, inconvenient and perhaps even offensive, but they help to protect us. They keep us one step ahead of an enemy whose versatility and ingenuity shows no signs of abating.

When liquid bombs jangled nerves in 2006, the west set about developing liquid bomb scanners. One such machine is being tested today in Albuquerque. Should it prove effective, we will once more be able to safely carry liquids in our hand luggage. Next in the limelight was the underpants bomb, which prompted authorities to roll out hugely controversial full-body scanners. Each of these measures has provoked a public reaction. Each can quite justly be ridiculed as ineffective when taken in isolation. But taken en masse – woven into a tapestry of good intelligence and behavioural profiling – they remain our only safety net. O'Leary and Broughton are wrong when they call shoe-checking "redundant". As long as al-Qaida is devoted to finding gaps in airport security, we must be devoted to plugging them.